International Journal of Oral Care and Research

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 7  |  Issue : 4  |  Page : 84--87

“Efficiency of removal of debris from root canal system with help of different irrigation system:” An in vitro scanning electron microscope study


Nikunj A Patel1, Kiran A Vachhani1, Md Muzammil Khan2, Anshu Gupta1, Prateek J Pachore1, Rajendra Bharatiya3,  
1 Department of Conservative Dentistry and Endodontics, Narsinhbhai Patel Dental College & Hospital, Visnagar, Gujarat, India
2 Department of Pedodontics and Preventive Dentistry, Bapuji Dental College & Hospital, Davangere, Karnataka, India
3 Department of Conservative Dentistry and Endodontics, AMC Dental College and Hospital, Ahmedabad, Gujarat, India

Correspondence Address:
Dr. Nikunj A Patel
Department of Conservative Dentistry and Endodontics, Narsinhbhai Patel Dental College & Hospital, S. P. Sahakar Vidyadham, Ambaji Gandhinagar Link Road, Near Kamana Char Rasta, Visnagar 384315, Gujarat.
India

Abstract

Aims and Objectives: The aim of this study was to determine the efficiency of EndoActivator, passive ultrasonic irrigation, side-vented needle, and syringe irrigation for removal of dentinal debris (smear layer) in root canals prepared with same master apical file sizes. Materials and Methods: Forty mandibular premolars with mature apices (extracted) were selected for this study. Each tooth was decoronated 2mm coronal to the cementoenamel junction with a diamond disk to facilitate straight-line access for instrumentation. Apical patency was determined by inserting an ISO # 08 K-file. Working length was determined by placing a size 15 K-file into the canal until it appeared at the apical foramen; this length was measured and the working length was set at 1mm short of this measurement. The roots were sealed with yellow sticky wax (DPI) to avoid apical extrusion during irrigation. The root canals were prepared to size 40, 0.02 taper, using step-back technique. After each instrument change, manual irrigation was performed with 2-mL NaOCl (3%) using a 26-gauge syringe. Then, a total of 40 samples were randomly distributed into four groups. According to group, root canals were irrigated with EndoActivator, passive ultrasonic irrigation, side-vented needle, and syringe irrigation. The roots were spilt and sent laboratory for examination under scanning electron microscope. Results: Ultrasonic irrigation had highest removal of the smear layer than the other irrigation systems followed by EndoActivator, side-vented needle, and syringe irrigation. Conclusion: Ultrasonic irrigation resulted in better removal of the smear layer in the apical third of root canals than EndoActivator, side-vented needle, and conventional needle irrigation.



How to cite this article:
Patel NA, Vachhani KA, Khan MM, Gupta A, Pachore PJ, Bharatiya R. “Efficiency of removal of debris from root canal system with help of different irrigation system:” An in vitro scanning electron microscope study.Int J Oral Care Res 2019;7:84-87


How to cite this URL:
Patel NA, Vachhani KA, Khan MM, Gupta A, Pachore PJ, Bharatiya R. “Efficiency of removal of debris from root canal system with help of different irrigation system:” An in vitro scanning electron microscope study. Int J Oral Care Res [serial online] 2019 [cited 2021 Dec 5 ];7:84-87
Available from: https://www.ijocr.org/text.asp?2019/7/4/84/271461


Full Text



 Introduction



Root canal treatment can be summarized as a series of procedures for cleaning, shaping, and obturation of root canal system. Chemomechanical preparation is one of the most important aspects of root canal treatment. Irrigation helps instruments to facilitate removal of debris, bacterial, and therapeutic material from root canal and uninstrumented areas such as isthmus, oval extension, and apical deltas.[1],[2]

Two important pillars of irrigation are tissue-dissolving ability and mechanical flushing action of irrigants. Walker reported sodium hypochloride (NaOCl) as root canal irrigant in 1936 and since then it has widely been accepted because of its antibacterial property and organic tissue-dissolving ability.[2],[3]

Conventional manual irrigation with a syringe and needle is widely accepted. Its flushing action depends on factors like diameter of needle, insertion depth, size and taper at prepared root canal hinder the exchange of irrigant and affect the debridement efficacy of irrigant. Different irrigant delivery devices increase the flow and distribution of irrigant within root canal system.[4],[5]

Acoustic streaming results from transmission of the energy at a freely oscillating file to the irrigant in the root canal during passive ultrasonic irrigation (PUI). It removes dentin debris and organic tissue from inaccessible areas of root canal.[1] EndoActivator (Dentsply Maillefer, Ballaigues, Switzerland) represents the sonic system with high-amplitude but low-frequency vibration. Mechanical oscillation produced at the tip at EndoActivator facilitates the removal of smear layer.[6]

Thus, to choose between different systems we must understand about the debris removal efficacy of different system. Thus, the purpose of this study was to compare the efficacy of EndoActivator, PUI, side-vented needle, and conventional syringe irrigation in removal of smear layer from root canal.

The null hypothesis stated that there was no significant difference in debris removal from root canals of teeth with the aforementioned irrigating systems.

 Materials and Methods



It is an in vitro scanning electron microscope (SEM) thesis study carried out at Department of Conservative Dentistry and Endodontics, Narsinhbhai Patel Dental College and Hospital, Visnagar, Gujarat, India, which was completed in a period of 3 months.

Forty freshly extracted mandibular premolars were selected for this study. All the teeth were thoroughly cleaned with an ultrasonic scaler and stored in 10% neutral buffered formalin solution for <1 week at room temperature as this will aid in disinfection of freshly extracted teeth and it will not alter the cutting characteristics of teeth.[7],[8]

All the teeth selected had matured root apices, extracted on periodontal and orthodontic ground, no caries, no restoration, and no previous endodontic treatment. All the teeth were decoronated 1mm above the cementoenamel junction (CEJ). The sectioned surfaces were flattened and smoothened with 2-mm grit abrasive paper.

Specimen preparation

The roots were endodontically instrumented 1 mm short of the apex with the step-back technique using K-file (Dentsply Maillefer) up to apical size ISO 40 after each instrument change, manual irrigation was performedNaOCl solution.

Experimental group distribution

After completion of preparation, samples were randomly assigned to experimental groups (n = 10) [Table 1].{Table 1}

All the samples were finally irrigated with 3mL of normal saline with a 26-gauge conventional needle and dried with absorbent paper points.

Sectioning of the sample

Deep grooves were made on the buccal and lingual surface of the root with diamond disks without perforating the canal. The roots were then split longitudinally using a chisel. One half of each root was selected for examination under SEM (Leo S–440i with Oxford energy dispersive X-ray analyzer [EDX] model 7060 with magnification from ×30 to ×3000000).

Scanning electron microscope evaluation

The specimens were examined under SEM under the magnification of ×2000, ×5000, and ×10000. The dentinal wall of apical third was observed for the presence or absence of smear layer and visualization of entrance to the dentinal tubules. Photomicrographs of the canal walls were taken at 2mm from apical foramen of each specimen and were evaluated individually by two previously calibrated examiners who were blind to irrigation regimen and attributed scores according to the rating system developed by Torabinejad et al.:[9]

0 = no smear layer, no smear layer on the root canal surface with all the tubule clean and open.

1 = moderate smear layer, outline of dentinal tubule visible or partially filled with debris.

2 = heavy smear layer, smear layer covers the root canal surface and the tubules.

 Results



The result of this study is noted in [Table 2].{Table 2}

The data were analyzed through the chi-squared test, which was applied to compare one group with another group and analysis of variance test was used to compare one group with rest all the groups, and from the observations of this study, following results were obtained:

The surfaces of root canals and the dentinal tubules in the apical thirds of samples in Groups A and B were relatively free of smear layer but there was mild smear layer in the apical thirds of the root canal surfaces in samples of Group A. There was no statistically significant difference between Groups A and B; however, the mean value for Group B was the lowest among all the smear layers than the other irrigation systems. The surfaces of root canals and the dentinal tubules in the apical thirds of samples in Groups C and D were with heavy smear layer.

 Discussion



The smear layer on the surface of instrumented root canal was described by McComb and Smith.[10] They suggested that the smear layer comprised dentin debris, the remnant of odontoblastic process, pulp tissue, and bacteria.[10]

The smear layer thickness was generally 1–2 µm according to Mader et al.[11] It comprises two parts: superficial smear layer and material packed into dentinal tubules up to depth of 40 µm.[11]

Huang et al.[12] stated that there is a statistically significant difference in removal of smear layer from coronal third and middle third by step-back technique and crown-down technique but no difference in apical region of root. Therefore, in this study root canals were prepared to size 40.2% taper using step-back technique. According to Ram,[13] canals need to be enlarged to size 40 for penetration of irrigant to apical third of root canal.

PUI works by transmission of acoustic energy from an oscillating file or smooth wire to an irrigant in the root canal. Transmission of this energy occurs by means of ultrasonic waves and it induces acoustic streaming and cavitation of the irrigant. A file should oscillate freely in prepared root canal to meet the principle of PUI. Therefore, file size 20 was used for PUI of root canal.[14]

Baumgartner and Cuenin[15] reported that NaOCl in concentration of 5.25%, 2.5%, and 1% efficiently removes predentin and pulpal remnants from the uninstrumented surfaces. Hence, 3% NaOCl was used as irrigant in this study. EndoActivator uses sonic energy for irrigation of the root canal. It is somewhat different from PUI because it operates at a lower frequency of 1–6 KHz as compared to ultrasonic (25–30 KHz).[16]

Stamos et al.[17] stated that PUI removed more dentin smear layer from the root canal than sonic irrigation. In a study by Sabins et al.,[18] passive activation of endodontic files for irrigation with sonic or ultrasonic energy in canals for as little as 30s after hand instrumentation produced canals with significantly less smear layer.

Extrusion of solution is prevented beyond apex with side-vented needle as it is with closed end. In a side-vented needle, irrigant is extruded beyond 1–1.5mm of a side-vented needle could have generated a liquid film along the air bubble–canal wall interface. Fluid stagnation in this “Deadwater zone” failed to provide adequate irrigant replacement resulting in gross debris retention. Therefore, more debris could be defected from all parts of canal walls. Hence, side-vented needle is less effective in removal of smear layer.[19]

The findings of this study are consistent with the findings of a number of other studies.[6],[20]

 Conclusion



Ultrasonic irrigation resulted in better removal of the smear layer in the apical third of root canals than EndoActivator, side-vented needle, and conventional needle irrigation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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